Hi Christian,As Dick pointed out, I did manage to bridge the gap.The area I am modelling covers four lod 8 cells, 2 up, 2 down. The raw file in my post above is the upper raw file. The bottom of this should join with the lower raw without a gap (it is also at the junction of 2 lod 5 areas). If you open the raw file posted above in a paint program and zoom in on the small filled area, you will see a 1 pixel gap to the edge of the image.I moved the whole image in the upper raw file down 1 pixel, and using dicks multisource suggestion, the gap was fixed.Thanks for the superb program, David.

Dick;A little off the subject but, I have given up on TerraScene. I would like to know a good source for Maps used in Ground2K. I could get 7.5 maps but that would be several hundred. Is their a place where say 1 Degree maps could be downloaded. It would be great if one could use LULC and DLG data or even Shape files.Richard;